As the mastermind behind the “Star Wars” saga, writer-director-creator George Lucas is often his own worst enemy. In retaking the reins of the films, his terrific eye for a storyline is undone by his tin ear for dialogue (remember Anakin’s “sand” speech from “Episode II: Attack of the Clones?”). His ability to stage impressive action scenes and manipulate special effects is almost negated by his awkward handling of actors. Thankfully, with “Star Wars Episode III: Revenge of the Sith,” the good George Lucas usually wins out, even if the story focuses on the Dark Side of the Force.

With this installment, Lucas benefits from maturing characters that give the performers more room to work. Anakin Skywalker (Hayden Christensen) now has weighty enough issues on his hands to justify his whining, and Ian McDiarmid is charmingly duplicitous as the corrupt Chancellor Palpatine a.k.a. Darth Sidious.

After rescuing Palpatine from the Sith Lord Count Duku (Christopher Lee), Anakin has recurring nightmares about his beloved Padme Amidalla (Natalie Portman). Anakin is already risking his status as a Jedi by having the relationship in the first place, and the thought of losing her is devastating to him.

He also has the unenviable task of trying to juggle his loyalty to his master Obi-Wan Kenobi (Ewan McGregor) and the Jedi council and his growing closeness to the Chancellor. The Jedi, particularly Mace Windu (Samuel L. Jackson) and Yoda (Frank Oz), are asking Anakin to spy on Palpatine in a manner that seems unbecoming to someone who’s supposed to be following the Light Side of the Force.

If you’ve been following the Star Wars saga with any kind of attention, you’re probably aware of what’s going to happen next. Fortunately, the obvious conclusion leads Lucas on a path where he can emphasize his strengths. No other film in the saga has more light saber duels or dogfights. As a result, we get less of the leaden exposition and more action.

It also doesn’t hurt that Christensen seems more at home in the role and appears to enjoy playing Anakin’s breakdown.

As usual, McGregor gives the best performance of the lot. He gleefully apes Alec Guinness’ mannerisms and has an easier time than some of the other performers getting around Lucas’ prose.

Some of the filmmaker’s vices are still readily apparent. Lucas simply can’t write a decent exchange between men and women in love. Padme and Anakin’s first words to each other are so wretched they inspire disbelief. The lines almost sink the credibility necessary to make the core relationship believable.

Nonetheless, there’s an energy and passion in “Revenge of the Sith” that’s been missing from the saga for some time. It may be more violent and less kid-friendly than its predecessors, but it’s a lot more involving.

In 1977, “Star Wars” made me fall in love with cinema. Without George Lucas, I don’t think I would have been able to later appreciate the work of filmmakers like Akira Kurosawa or Luis Buñuel.

For the last few years, Lucas’ mishandling of his own story almost made me forget how thrilling the “Star Wars” films could be. “Revenge of the Sith” is downbeat, but it’s a happy reminder of what happens when Lucas has the Force on his side.